9/30/18

How to Make a Wooden Bearing Pack


Some of my designs use phenolic tube for making a simple and easy to align bearing pack allowing for very free moving arbors and pendulums. 

Phenolic tube is easily available and inexpensive in the U.S., but I have recently found that this may not be the case for some other countries.

The following suggestion came from fellow builder Adrian Iredale in Australia – a country with apparently a copious phenolic scarcity.

If your country also is suffering from a dearth of phenolic tubes, or even if you live in a phenolic abundant country and would just like to try your hand at building a wooden bearing pack, here are the instructions and pictures on;

How to Make a Wooden Bearing Pack
to fit 3/8”OD, 3/16”ID, 1/8thickness bearings.  Metric equivalents may be substituted.


I didn't take a picture of this, but the first step is to cut the 1/2” (12mm) dowel to the correct length as described in the plans and then chuck the dowel into a hand drill.  Get the drill spinning and mark the center with a pencil - or find some other way to find the exact center of the dowel.

1)      This picture shows the Jig holding the dowel.  To make this Jig, using your drill press, drill a perfectly vertical hole in a large block of wood to hold a 1/2” (12mm) wood dowel. Then insert a 1/2” dowel of the correct length for your bearing pack into the vertical Jig and center drill the dowel with a 3/8” (10mm) brad point drill bit 1/8” (3mm) deep. 

2)      Flip the 1/2” dowel over 180* and drill the other end the same way.
3)      Then center drill through from both ends with a 1/4” (6mm) metal twist drill.  The metal twist drill will center itself better in the center depression that was left by the original 3/8" brad point.  Note that drilling the dowel from both ends halfway through will better center the 1/4” hole than drilling all the way through from only one side.
4)      Your wooden bearing pack is now ready to load in the bearings.
5)      Bearings are pressed into place at both ends.
6)      The 3/16” (5mm) brass rod may need some reduction in its diameter to fit easily into some bearings.  I used 220 sandpaper on a 3/16” brass rod that was chucked and spinning in the drill press.  Test frequently for a good bearing fit.

7)      Then the sanded-to-fit 3/16” rod was polished with buffing compound inside a folded leather strop.

Note that all drill bits are not created equally.  In picture 2 you will see that I am using my now famous and inexpensively priced “Wobble Point” Vermont American brad point drill bit.  That is because I want the bearing to be a press fit into the wood, and this bit cuts a tight 3/8” hole, whereas my expensive Lee Valley brad point bits all tend to cut holes that are a bit oversized which would create a hole into which the bearing may fit too loosely.

Wood dowels are also not created equally.  To be sure that I find a well fitting 1/2" dowel I would first drill a 1/2" hole in a piece of scrap ply and take the scrap to the hardware store.  With this procedure I am sure that I will find a nice round, straight, snug-fitting dowel that fits the hole correctly.

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I love comments, but in order for me to have more time playing in my sawdust, I cannot respond to them here. If you have a technical question, please do not post it here, or I will have my wife answer it for me and her technical knowledge is highly suspect. For technical questions, check out the FAQ section of my website, or find my email link there. Mahalo and Aloha, Clayton